Insulation resistance detecting apparatus, system having the same, and method thereof

Patent metadata

Field	Value
Publication number	US-12181509-B2
Application number	US-202117483012-A
Country	US
Kind code	B2
Filing date	Sep 23, 2021
Priority date	Jan 11, 2021
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

An insulation resistance detection apparatus includes a processor configured to separate a fuel cell from a high voltage battery depending on an insulation resistance value of a vehicle during driving of the vehicle, and then to measure an insulation resistance value of the fuel cell to determine whether it is a failure of the fuel cell or a failure of the high voltage battery, and when it is the failure of the fuel cell, to determine a cause of the failure by calculating an insulation resistance variation; and a storage configured to store data and algorithms driven by the processor.

First claim

The invention claimed is:

1. An insulation resistance detection apparatus comprising:
a processor configured to separate a fuel cell from a high voltage battery, by a main relay circuit, based on an insulation resistance value of a vehicle during driving of the vehicle, and to measure an insulation resistance value of the fuel cell with the fuel cell and high-voltage battery separated, by using an insulation resistance measurement device, to determine whether a failure of the fuel cell is present or a failure of the high voltage battery is present, and when the failure of the fuel cell is present, to determine a cause of the failure by calculating a variation of insulation resistance; and
a storage configured to store data and algorithms driven by the processor;
wherein the processor maintains an open circuit voltage (OCV) state by blocking a stack current of the fuel cell when the insulation resistance value of the vehicle is smaller than a predetermined reference value.

2. The insulation resistance detection apparatus of claim 1 , wherein the processor calculates an average value of insulation resistance values of the vehicle and stores the average insulation resistance value in the storage during starting off of the vehicle.

3. The insulation resistance detection apparatus of claim 2 , wherein the processor turns off a main relay connected between the fuel cell and the high voltage battery when the insulation resistance value of the vehicle is smaller than a predetermined reference value.

4. The insulation resistance detection apparatus of claim 3 , wherein the processor compares the insulation resistance value of the fuel cell with a predetermined reference value in a state in which the main relay is turned off.

5. The insulation resistance detection apparatus of claim 4 , wherein the processor determines that the failure due to insulation resistance of the high voltage battery exists when the insulation resistance value of the fuel cell is equal to or greater than the reference value.

6. The insulation resistance detection apparatus of claim 4 , wherein the processor, when the insulation resistance value of the fuel cell is smaller than the predetermined reference value,
calculates a difference value between the average insulation resistance value and the insulation resistance value of the fuel cell as the variation of insulation resistance.

7. The insulation resistance detection apparatus of claim 6 , wherein the processor compares the variation of insulation resistance and a predetermined variation reference value to determine that the a failure of insulation resistance due to an increase in ionic conductivity exists when the insulation resistance variation is smaller than the variation reference value, and to determine that the failure due to insulation breakdown of the fuel cell exists when the insulation resistance variation is equal to or greater than the variation reference value.

8. The insulation resistance detection apparatus of claim 7 , wherein the processor notifies replacement of an ion filter when it is determined that the failure of insulation resistance is due to the increase in ionic conductivity.

9. The insulation resistance detection apparatus of claim 6 , wherein the processor determines that the failure due to insulation breakdown of the fuel cell exists when the insulation resistance value rapidly changes, and determines that the failure of insulation resistance due to an increase in ionic conductivity exists when the insulation resistance value smoothly changes.

10. A vehicle system comprising:
a fuel cell configured to supply power;
a high voltage battery configured to charge and discharge;
a main delay positioned between the fuel cell and the high voltage battery;
a first insulation resistance measurement device connected to an output terminal of the fuel cell to measure an insulation resistance value of the fuel cell;
a second insulation resistance measurement device connected to an output terminal of the high voltage battery to measure an insulation resistance value of the high voltage battery; and
an insulation resistance detection apparatus configured to separate a fuel cell from a high voltage battery based on an insulation resistance value of a vehicle during driving of the vehicle, and to determine whether a failure of the fuel cell is present or a failure of the high voltage battery is present, and when the failure of the fuel cell is present using the insulation resistance value measured when the fuel cell and high voltage battery are separated, to determine a cause of the failure by calculating a variation of insulation resistance;
wherein the insulation resistance detection apparatus turns off a main relay connected between the fuel cell and the high voltage battery when the insulation resistance value of the vehicle is smaller than a predetermined reference value, and controls the first insulation resistance measurement device to measure the insulation resistance value of the fuel cell.

11. The vehicle system of claim 10 , wherein the insulation resistance detection apparatus determines that the failure due to insulation resistance of the high voltage battery is present when the insulation resistance value of the fuel cell is equal to or greater than the reference value, and calculates the variation of insulation resistance when the insulation resistance value of the fuel cell is smaller than the reference value.

12. The vehicle system of claim 11 , wherein the insulation resistance detection apparatus calculate an average value of insulation resistance values of the vehicle and store the average insulation resistance value in the storage when starting off the vehicle, and calculates a difference value between the average insulation resistance value and the insulation resistance value of the fuel cell as the variation of insulation resistance.

13. An insulation resistance detection method comprising:
separating, by a main relay circuit, a fuel cell from a high voltage battery based on an insulation resistance value of a vehicle during driving of the vehicle;
determining, by using an insulation resistance measurement device, whether a failure of the fuel cell is present or a failure of the high voltage battery is present by measuring the insulation resistance value of the fuel cell with the fuel cell and high-voltage battery separated; and
determining, by the insulation resistance measurement device, a cause of the failure by calculating a variation of insulation resistance when the failure of the fuel cell is present;
wherein the separating of the fuel cell and the high voltage battery includes:
maintaining an open circuit voltage (OCV) state by blocking a stack current of the fuel cell when the insulation resistance value of the vehicle is smaller than a predetermined reference value; and
turning off a main relay connected between the fuel cell and the high voltage battery.

14. The insulation resistance detection method of claim 13 , further comprising calculating an average value of insulation resistance values of the vehicle and store the average insulation resistance value in the storage when starting off the vehicle.

15. The insulation resistance detection method of claim 13 , wherein the determining of whether the failure of the fuel cell is present or the failure of the high voltage battery is present includes:
determining whether the insulation resistance value of the fuel cell is smaller than the reference value in a state where the main relay is turned off; and
determining that the a failure due to insulation resistance of the high voltage battery is pres

Assignees

• Hyundai Motor Co Ltd
• Kia Corp

Inventors

• Park Hyo Jin
• Kweon Soon Gil
• Kim Min Taek

Classifications

• Y02E60/50

  Fuel cells · CPC title

• H01M10/48

  Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569) · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• B60W2510/242

  for electrical energy · CPC title

• H01M8/04671

  of the individual fuel cell · CPC title